| |
Acromegaly is caused by an excess of growth hormone. The most obvious sign of acromegaly is the overgrowth of bones in the face, hands and feet. However, the changes occur so slowly that they go unnoticed on a daily basis.
Acromegaly usually develops after the person has reached physical maturity. People between 30 and 50 years are most commonly affected. About 1,000 people in Australia are estimated to have acromegaly.
A non-cancerous (benign) tumour on the pituitary gland is the most common cause. The pituitary gland, located in the brain, makes a number of chemicals including growth hormone. Growth hormone influences a person’s height and metabolism, and assists the body to make bone and muscle.
Symptoms
The symptoms and signs of acromegaly can include:
- Swelling of soft tissue in the hands and feet (onset signs)
- Enlarged bones in the skull, face, jaw, hands and feet
- Headaches
- Gaps forming between the teeth, which may cause a ‘bad bite’
- Barrel chest
- Enlarged heart (cardiomegaly)
- Thick, oily and coarse skin
- Growth of skin ‘tags’
- Overgrowth of hair
- Husky voice
- Enlarged tongue and lips
- Snoring or drooling while asleep
- Heavy sweating (hyperhidrosis)
- Strong body odour
- Weakening of the muscles in the arms and legs
- Menstrual cycle problems
- Discharge from the nipples (in both women and men)
- Vision changes, such as loss of peripheral (side) vision.
Complications of acromegaly
Without medical treatment, acromegaly can cause a range of complications including:
- Regular stopping of breathing while asleep (sleep apnoea)
- Arthritis
- Carpal tunnel syndrome
- Osteoporosis
- Osteoporotic fractures
- Diabetes
- High blood pressure (hypertension)
- Heart disease
- Premature death.
Causes
A pituitary tumour (adenoma) causes about 90 per cent of acromegaly cases. The adenoma prompts the pituitary gland to make excessive amounts of growth hormone. This affects many tissues of the body including the bones and skin.
The adenoma slowly enlarges and presses against the surrounding brain tissue. This can cause vision problems as the tumour cramps the optic (eye) nerves.
The hormone imbalance usually causes irregularities in other hormonal systems. For example, an affected person may develop diabetes. Affected women can have menstrual cycle irregularities. Both women and men with acromegaly may have nipple discharge caused by hormonal changes to breast tissue.
Progress of the condition depends on tumour size
The progression of acromegaly depends on the size of the tumour. In general, acromegaly progresses faster and more aggressively in people who develop a pituitary tumour early in adult life. The cause of pituitary tumours is unknown. A genetic mutation that occurs at the time of conception is thought to be the cause. Without a known cause, it is impossible to predict or prevent acromegaly.
Other causes
Certain tumours in other organs, such as the lungs or pancreas, can sometimes cause acromegaly. These tumours either make growth hormone or make a chemical called growth hormone-releasing hormone (GHRH) that prompts the pituitary gland to make growth hormone.
Diagnosis
Acromegaly is difficult to diagnose in its early stages because the physical changes occur over many years. Diagnosis of acromegaly may include:
- Medical history
- Physical examination
- Blood test to check growth hormone (HGH) levels
- Oral glucose test – this tests whether the level of growth hormone is lowered by the glucose. Normally the growth hormone is lowered. When someone has acromegaly, it will not be lowered and may even rise. The blood glucose level will also be checked because, in people with acromegaly, the glucose level may be higher than normal due to impaired glucose tolerance.
- Scans (such as CT or MRI) to check the size of the pituitary gland.
Treatment
Medical treatment can reduce swelling of the soft tissue in the face, hands and feet, but cannot reverse the effects of acromegaly on the bones. Treatment aims to remove the pituitary tumour, reduce the risk of complications and prevent the acromegaly from getting worse. Options may include:
- Drugs – to shrink the pituitary gland and block or inhibit its ability to make growth hormone. Drugs may be used as the first line of treatment in elderly patients, or may be used to shrink the pituitary tumour prior to surgery.
- Surgery – to remove the pituitary tumour. In most cases, surgery can be performed through the patient’s nose. More than one operation may be needed depending on the size of the tumour.
- Radiation therapy – to shrink the pituitary tumour. Radiation therapy may be recommended after surgery.
The doctor may choose one or more treatments. However, the pituitary tumour may grow back, despite successful treatment. Further medical treatment may be needed.
Ongoing tests
A person with acromegaly should have regular medical tests to monitor the condition. Tests may include an annual medical checkup and blood tests to measure growth hormone levels.
Where to get help
- Your doctor
- Endocrinologist (doctor that specialises in hormone problems)
- Australian Pituitary Foundation, Victorian office Tel. 1300 331 807
Things to remember
- Acromegaly is a condition caused by an excess of growth hormone, which causes the overgrowth of bones in the face, hands and feet.
- A tumour on the pituitary gland is the most common cause of acromegaly.
- Medical treatment aims to remove the pituitary tumour, reduce the risk of complications and prevent the acromegaly from getting worse.
You might also be interested in:
Growth hormone.
Hormonal (endocrine) system.
Want to know more?
Go to More information for support groups, related links and references.
|  |
|
